喷气织机辅喷嘴气流场数值模拟及特性分析

采用k-ε双方程湍流模型对喷气织机辅喷嘴喷射气流场进行了数值计算。分别比较了不同输入气压、不同辅喷嘴出口截面积及不同出口形状情况下,辅喷嘴气流的特性变化。流动数值计算表明:输入气压越大,辅喷嘴喷射气流速度也越大;在辅喷嘴出口处将产生膨胀波,其气流马赫数大小与输入气压呈线性关系;出口截面积大小能影响喷射气流的速度和紊流强度,需考虑其最佳值;相同截面积下,不同辅喷嘴出口形状对其外流场产生的影响很小。数值计算结果与理论值和实验结果对照表明,利用数值计算方法模拟辅喷嘴气流场具有一定的可行性,这将为进一步开展辅喷嘴的流动特性研究及喷气织机的研制提供参考。

Numerical Simulation and Analysis on Gas Flow Field of the Auxiliary Nozzle in Air-Jet Looms

Using k-ε dual-equation turbulence model,the gas flow field of the auxiliary nozzle in air-jet looms was analyzed.The character change of the gas flow was compared at different conditions,e.g.the input air pressure,the section area and the outlet shape of auxiliary nozzle.The result of numerical calculation showed that the jet speed of the airflow from the auxiliary nozzle was improved if the input air pressure was increased.The expansion wave appeared at the exit of auxiliary nozzle and there was a linear relationship between flow mach number and the input air pressure.The optimal outlet section area needs to be considered because it can influence the speed of the airflow jet and the turbulence intensity.Different outlet shape of auxiliary nozzle had few influences on the producing of gas flow field with the same outlet section area.The numerical calculation result,which was compared with the theoretical value and experimental value,showed that it was feasible to simulate the gas flow field of the Auxiliary nozzle,and provided some references for character study of the auxiliary nozzle and design of the air-jet loom.